Antonyms of verb stiffen

2 of 3 senses of stiffen

Sense 1
stiffen -- (become stiff or stiffer; "He stiffened when he saw his boss enter the room")
       Antonym of loosen (Sense 7)
      => loosen, relax, loose -- (become loose or looser or less tight; "The noose loosened"; "the rope relaxed")

Sense 2
stiffen -- (make stiff or stiffer; "Stiffen the cream by adding gelatine")
       Antonym of loosen (Sense 1)
      => loosen, loose -- (make loose or looser; "loosen the tension on a rope")

Synonyms/Hypernyms (Ordered by Estimated Frequency) of verb stiffen

3 senses of stiffen

Sense 1
stiffen -- (become stiff or stiffer; "He stiffened when he saw his boss enter the room")
       => change -- (undergo a change; become different in essence; losing one's or its original nature; "She changed completely as she grew older"; "The weather changed last night")

Sense 2
stiffen -- (make stiff or stiffer; "Stiffen the cream by adding gelatine")
       => change, alter, modify -- (cause to change; make different; cause a transformation; "The advent of the automobile may have altered the growth pattern of the city"; "The discussion has changed my thinking about the issue")

Sense 3
stiffen, tighten, tighten up, constrain -- (restrict; "Tighten the rules"; "stiffen the regulations")
       => restrict, restrain, trammel, limit, bound, confine, throttle -- (place limits on (extent or access); "restrict the use of this parking lot"; "limit the time you can spend with your friends")